This invention relates to a deformable, radiation image display element, particularly adapted to be used in connection with an X-ray apparatus.
In conventional radiation imaging apparatuses, such as an X-ray apparatus, the medical diagnosis of human body ailments or the non-destructive inspection of objects is performed after transforming the radiation image of the body or object into a permanent hard copy form by the use of an X-ray silver salt film or xeroradiography. Accordingly, considerable time is required to obtain a visually usable output from an X-ray irradiation, and such delay is at the least inconvenient and at the most even dangerous in an emergency situation.
An instant photographic image display device has been developed in the prior art, as shown in FIG. 1 and disclosed in detail in Japanese patent application Ser. No. 13189/1972. In this device, an electrostatically deformable element 16 is fabricated by covering a transparent base plate 11 with a laminate which consists sequentially of a transparent electrically conductive layer 12, a photoconductive layer 13, and a deformable elastomer layer 14. When this element is exposed to an optical image 15, with the transparent conductive layer 12 being grounded and a uniform charge distribution 17 being imparted to the surface of elastomer layer 14, then an electrostatic charge distribution corresponding to the image pattern is formed on the interface between the elastomer layer 14 and the photoconductive layer 13. Simultaneously, the optically exposed portions of the surface of the elastomer layer 14 are deformed as equilibrium is established between the electrostatic force and the elasticity of the elastomer. The deformation image thus obtained on the surface of the elastomer layer 14 is visually viewable by the use of a Schlieren optical system or other suitable readout system as illustrated in FIG. 3. In such a system, when light is radiated from a source L through suitable lenses onto the surface of an elastomer layer where a deformation image has been formed at a position labeled E, a visual reproduction of the optical image is obtained on a projection screen 9.